I have not seen anyone do this quick analysis. $487 a month is $5,844 a year. While 4% of $73,000 is $2,920 a year. This is 50% reduction. Then you need to decide if the pension is good through your lifetime. You might want to think about your heirs and what the $73,000 could grow to vs the $5844 pension (minus 12% tax for my calculation, could be more) or $5,143.I have 10 years of service at Boeing, which will result in a pension of ~$487/month, starting early next year when I turn 65. Or I could take a lump sum of $73k.
So, $5,143 invested per year for 20 years at 10% is $324,000 and $73,000 invested over 20 years at 10% is $491,000.